酵母菌YPL014W蛋白之功能特徵分析

Functional characterization of yeast YPL014W

林季瑩(Chi-Ying Lin)

指導教授 ： 鄧述諄

國立臺灣大學/醫學院/微生物學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.01623

摘要

酵母菌主要是藉由端粒酵素來複製端粒。當端粒酵素缺乏時，細胞會逐漸走向老化 (senescence)、死亡，只有少數細胞可以倖存。這些倖存細胞主要是藉由選擇性重組路徑(alternative recombination pathway)來延長端粒。YPL014W在細胞老化、重組作用發生的過程中表現量上升。由於Ypl014w可與Cdc28、Cln3等細胞週期蛋白結合，為Cdc28蛋白複合體（Cdc28p-associated complex）的一部份，所以我們藉由研究對ypl014w△突變株及cln3△ypl014w△突變株的生長特徵分析、YPL014W 的轉錄是否受到葡萄糖的影響以及Ypl014w是否會影響葡萄糖所引起的CLN3 mRNA的表現量上升、Ypl014w對Cln3-Cdc28激酶活性之影響，來探討Ypl014w可能的功能。在外觀型態及細胞週期分析實驗中，我們發現YPL014W會影響細胞週期的分佈，而此影響可能是藉由影響Cln3來達成。在生長速率的研究中，YPL014W的剔除則對於細胞生長速率並沒有影響。在YPL014W與葡萄糖調控的實驗裡，發現YPL014W的轉錄會受到葡萄糖的影響而YPL014W並不會影響由葡萄糖所引起的CLN3 mRNA的表現量上升。藉由生長特徵分析及Ypl014w與葡萄糖相關的研究，我們已初步觀察到Ypl014w在細胞週期與葡萄糖調控上的影響。

關鍵字

細胞週期 ； 酵母菌 ； 葡萄糖

並列摘要

Telomeres is replicated by telomerase in budding yeast. Most cells that lack telomerase enter into senescence and eventually die. However, a few cells bypass the senescence phenotype and survive. These survivors elongate their telomeres by the alternative recombination pathway. The transcriptional level of YPL014W is increased during this elongation process. YPL014W associates with two cell cycle proteins, Cln3 and Cdc28. Here we analyzed the growth characteristics of the ypl014w△ mutant and cln3△ypl014w△ double mutant. In addition, we also investigated whether Ypl014w affects on the glucose regulation of Cln3, Cln3-Cdc28 kinase activity. Analysis of cell morphology and cell cycle revealed that the ypl014w△ mutant accumulates in the G2 phase of the cell cycle, wherever the cln3△ypl014w△ double mutant accumulates in the G1 phase. These data suggest that Ypl014w may involve in cell cycle regulation through Cln3. In the assay of glucose regulation of YPL014W, we found that glucose affects the transcription of YPL014W and Ypl014w has no influence on the glucose regulation of CLN3.Our findings suggest that Ypl014w may involve in cell cycle and glucose regulation.

並列關鍵字

Cell Cycle ； Yeast ； Glucose ； CLN3 ； YPL014W

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